Microstructure/processing relationships in high-energy high-rate consolidated powder composites of Nb-stabilized Ti3Al+TiAl

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5095987

Persad, C; Lee, B; Hou, C; Eliezer, Z; Marcus, H L

A new approach to powder processing is employed in forming titanium aluminide composites. The processing consists of internal heating of a customized powder blend by a fast electrical discharge of a homopolar generator. The high-energy high-rate '1MJ in 1s' pulse permits rapid heating of an electrically conducting powder mixture in a cold wall die. This short time at temperature approach offers the opportunity to control phase transformations and the degree of microstructural coarsening not readily possible with standard powder-processing approaches. This paper describes the consolidation results of titanium aluminide-based powder-composite materials. The focus of this study was the definition of microstructure/processing relationships for each of the composite constituents, first as monoliths and then in composite forms. Non-equilibrium phases present in rapidly solidified TiAl powders are transformed to metastable intermediates en route to the equilibrium gamma phase.

• Research Organization: Texas Univ., Austin, TX (USA). Center for Materials Science and Engineering
• OSTI ID: 5095987
• Report Number(s): AD-A-213524/2/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360601* -- Other Materials-- Preparation & Manufacture
ALLOYS
ALUMINIUM ALLOYS
COMPOSITE MATERIALS
CONTROL
CRYSTAL STRUCTURE
DIES
DISPERSIONS
ELECTRIC DISCHARGES
ELECTRIC GENERATORS
ELECTROMAGNETIC RADIATION
EQUILIBRIUM
GAMMA RADIATION
HEATING
IONIZING RADIATIONS
MATERIALS
MATRIX MATERIALS
METALLURGICAL EFFECTS
METALLURGY
MICROSTRUCTURE
MIXTURES
NIOBIUM ADDITIONS
NIOBIUM ALLOYS
PHASE TRANSFORMATIONS
POWDER METALLURGY
PROCESSING
RADIATIONS
TITANIUM ALLOYS
WALLS